Innovation inspired by insects

They clamber over any terrain, scaling obstacles many times their height with ease. This has fascinated robotics scientists for two decades. By studying the way cockroaches move, researchers have been able to build six-legged robots that are relatively stable on rough terrain.

Until recently, research focused on observing the way the insects moved and on making machines that emulated it. But now an Israeli researcher is planning to take this further by finding out how the cockroach brain is involved (or not) in the movements.

Amir Ayali from Tel Aviv University reckons that his approach will lead to lighter, more efficient robots. This is because the cockroach does not ‘think’ about its leg movements; they happen instinctively.

If roboticists could copy this instinctive behaviour where the legs respond to their environment without the roach having to think about it, less computing power would be needed for movement, and so the robot would be lighter and faster on its six little legs.

In another strand of research, scientists at North Carolina State University tried merging insect with machine, creating a cyborg cockroach. After implanting electrodes into the insect's antennae and rear-end sensory appendages called cerci, the researchers could send electrical impulses to simulate an obstacle in front of the insect or the sensation of something creeping up behind it, and thereby control its movements.

In California, researchers at the University of California, Irvine, attached a cockroach to transmitters and sat it on a free-moving ping-pong ball atop a small, wheeled buggy. Using electrical signals, the researchers could cause the cockroach to respond and move its legs in particular ways; in turn, these movements on the ping-pong ball drove the buggy.

One potential use of these studies is to have remote-controlled cockroaches carry cameras or sensors into dangerous places such as buildings wrecked by explosions or earthquakes.

Insect eyes have long fascinated scientists, partly because they are very different from our own. Instead of having one central lens per eye, insects have a large array of tiny lenses held together to form a ‘compound eye’.

The insect sees a mosaic of all the images from these lenses – resulting in sight that may not be as focused as ours, but is far more sensitive to movement and provides a 360-degree field of vision.

Some recent research has focused on the way the compound eyes of moths tend to capture light rather than reflect it. This helps these creatures see at night when they are most active but little light is available.

It also helps them avoid being eaten, as they would be more visible if their eyes shone in the moonlight. Scientists at the City University of New York, in collaboration with Massachusetts Institute of Technology and New York University, have created a new type of ‘nanomaterial’ based on the structure of the moth's compound eye, consisting of crystals encrusted with pyramid-shaped bumps of silicon nitride.

Incorporated in medical scanning equipment, this material can capture energy normally lost from X-rays and thereby improve the resolution and accuracy of images – and, in turn, allow X-ray doses to be reduced.